An international water law is an agreement between two or more nations that regulates activity on the seas. Most international laws come into effect after the participating nations sign a treaty. A treaty is an international agreement between two or more nations in written form and governed by international law.

United Nations Law of the Sea

Until the twentieth century, nations did not have the ability to protect their coastlines and waters for a great distance. Nations also did not require or have the ability to use vast amounts of ocean resources, such as fish or crude oil. For these reasons nations observed only a 3-mile (4.8-kilometer) territorial water zone until 1900. A territorial water zone is an area off the coast or on a nation’s border in which a nation can defend and enforce its laws.

By 1850, military progress enabled nations to defend waters far beyond the traditional 3 mile (4.8 kilometer) territorial waters. Modern fishing ships also had the ability to remain at sea for months at a time and catch tons of fish. These developments led many nations to consider extending their territorial waters.

After the discovery of oil and natural gas deposits under the ocean floor, the United States, in 1945, became the first nation to abandon the 3-mile (4.8 kilometer) territorial waters limit. Other nations soon joined the race to claim as much of the ocean and its resources as they could.

For several decades nations made different claims on their water laws and how they would enforce those laws. This multitude of laws caused confusion among cargo ships and naval vessels. Realizing the need for standard laws, the United Nations held the Third United Nations Conference on the Law of the Sea in 1973.

The United Nations is an international organization of nations designed to promote peace and security. The goals of this conference were to define a modern limit for territorial waters and develop international laws of navigation rights. Navigation rights involve whether or not a country will allow ships from another country to pass through its territorial waters.

After nearly a decade of debate the conference produced the United Nations Law of the Sea in 1982. The United Nations Law of the Sea established a structure within which all maritime activities may occur. The Law of the Sea defined territorial waters as extending for 12 miles (19.3 kilometers) from a coastal nation’s shoreline. Nations are free to enforce their laws within their territorial waters. Essentially territorial waters are part of that nation.

The Law of the Sea also contained a provision for “exclusive economic zones.” An exclusive economic zone is an area that extends for 200 miles (322 kilometers) from a nation’s coast. A nation has the right to all of the natural resources contained within its exclusive economic zone, including fishing rights, and oil and gas rights.

The United Nations Law of the Seas also addressed the right of ships to navigate the seas. Nations with large navies were concerned that an increase of territorial waters to 12 miles (19.3 kilometers) would limit the free movement of naval ships.

A 12-mile (19.3-kilometer) territorial jurisdiction zone would have allowed many smaller nations to block ships from passing through strategically important straits, forcing the vessels to travel hundreds or thousands of miles (kilometers) as a detour. A strait is a narrow body of water that connects two larger bodies of water. For example, either Spain or Morocco could have blocked access to the Mediterranean Sea from the Atlantic by preventing ships from passing through the Strait of Gibraltar, which is only 8 miles (13 kilometers) wide.

Also, nations made up of many islands, such as the Philippines or Indonesia, could have forced ships to travel thousands of miles (kilometers) to go around all of their islands. Each island would have had its own 12-mile (19.3-kilometer) territorial water zone. To avoid such divisive issues the Convention allows for transit passage through another country’s territorial waters with few restrictions.

The Law of the Sea has been modified several times. These changes speak to new issues as they arise. Perhaps the most important change to the Law of the Sea was the Convention relating to the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks in 1995. This law addressed one of the major holes in the original Law of the Sea. Large groups, or schools, of fish migrate. Migration is seasonal travel over great distances. The actions of one country could greatly affect another country.

If one country overfished (caught too many fish) a large school of fish, then other countries would be affected when the fish moved into their waters. The Convention relating to the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks set limits on how much fish a country could take from schools of fish.

The Law of the Sea set up a unique method of enforcement, which is a way of making sure that everyone obeys the law. Every nation that participates in the Law of the Sea agrees to a process called arbitration. During arbitration the nations that have a disagreement go before an independent party, who presides like a judge.

After hearing from the disagreeing nations, the independent party decides what to do about the situation. Under the terms of the Law of the Sea, the disagreeing nations are then bound by this decision. As of mid-2004, 144 nations have ratified (approved and adopted) the Law of the Sea.

The United States announced a proclamation in 1982 containing some similarities to the Law of the Sea, including a 200-mile exclusive economic zone, but has not ratified the Law of the Sea. Opponents question the practicality of giving the United Nations authority to make laws in a sovereign (independent) country’s territorial waters.

United Nations Environment Program

In 1973 the United Nations Environment Program began to seek ways to prevent destruction of the ocean environment. The United Nations Environment Program helps nations within a particular region of the world solve problems that are unique to that area. The United Nations Environment Program formed the Regional Seas Conventions.

The Regional Seas Conventions are a series of agreements between nations. Each agreement has two or more participating nations. Each agreement addresses environmental problems that are of major concern in that particular part of the world.

Other international water laws

The United Nations has passed numerous other international water laws. The International Convention for the Regulation of Whaling addresses the issue of killing whales. Whales migrate over vast areas of the ocean. Overwhaling in the past 200 years brought many species of whales near extinction. The International Convention for the Regulation of Whaling prohibits whaling, except in limited circumstances.

Other international laws under the United Nations include the Convention on the Transboundary Movement of Hazardous Wastes (Basel Convention), and the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matters (London Dumping Convention). The Basel Convention addresses the safety of dangerous cargo that is transported over the seas. The London Dumping Convention seeks to prevent nations from dumping their trash and chemicals into the oceans.

Another major focus of international water laws is the right to use rivers. Freshwater is rare in many parts of the world. An important river might flow through several countries, providing people with water for drinking and irrigation (watering crops). Over the last century increases in population and economic development have led nations to use more freshwater. If a country upstream uses too much water from a river, then that river might only be a trickle when it reaches a country downstream.

India and Pakistan for instance, have been at odds for over 50 years regarding the use of the Indus River, which flows from India to Pakistan. In 1960, India and Pakistan signed the Indus Water Treaty. Problems have continued however, with Pakistan claiming violations of the treaty by India.